If you have complex view logic, this can easily lead to helper methods which call each other. See how to refactor this out into another object in this episode. This is also known as the presenter pattern.
(7 minutes)

In order to improve performance of your Rails application you need to find the bottlenecks. A great starting point is your production log. In this episode you will see how to use RAWK to analyze your log file and determine which controller actions take up the most processing time.
(5 minutes)